Audio/Video Synchronization Using Audio Hashing

1. A method, comprising: receiving an audio signal and a corresponding video signal; applying a data reduction technique to the audio signal to derive a digital signature that identifies the audio signal; transmitting the audio signal to a receiver via an audio network; and transmitting the video signal and the audio digital signature to the receiver via a digital network wherein the audio digital signature is included in a SIP (Session Initiation Protocol) packet with a corresponding video frame number, and wherein the method is performed by a processor.

2. The method as recited in claim 1 , wherein the video signal and the audio digital signature are transmitted over separate channels of the digital network.

3. The method as recited in claim 1 , further comprising combining the audio digital signature with the video signal for transmission over the digital network.

4. The method as recited in claim 3 , wherein the combining further comprises combining the audio digital signature with a Real-time Transport Protocol (RTP) video packet.

5. The method as recited in claim 3 , wherein the combining further comprises appending the audio digital signature to a payload portion of an RTVideo packet.

6. The method as recited in claim 3 , wherein the combining further comprises embedding the audio digital signature in a header extension of an RTP video packet.

7. The method as recited in claim 1 , wherein the data reduction technique further comprises a hashing function.

8. The method as recited in claim 1 , wherein the data reduction technique further comprises a Mel-Frequency Cepstral Coefficients (MFCC) method to the audio signal.

9. The method as recited in claim 1 , wherein the steps of the method are performed for each of multiple frames of the audio signal and corresponding multiple frames of the video signal.

10. A system, comprising: audio reception means for receiving multiple frames of an audio signal via an audio network, the audio signal including an original audio signal and one or more additional audio signals; hashing means for deriving a mixed hash value of each audio frame by applying a hashing function to the audio signal contained within the audio frame; video reception means for receiving multiple frames of a video signal via a digital network, each video frame corresponding to an audio frame of the audio signal; means for receiving multiple unmixed hash values via the digital network wherein at least one of the unmixed hash values are included in a SIP (Session Initiation Protocol) packet with a corresponding video frame number, there being an unmixed hash value corresponding to each video frame, the unmixed hash value for a video frame being derived by applying the hashing function to a corresponding frame of the original audio signal; correlation means for correlating a mixed hash value with an unmixed hash value to identify a video frame associated with the unmixed hash value that corresponds to an audio frame associated with the mixed hash value; and rendering means for rendering the correlated audio frame and video frame in synchronicity.

11. The system as recited in claim 10 , wherein the video frames and the unmixed hash values are received over different channels of the digital network.

12. The system as recited in claim 10 , wherein the unmixed hash value is included with the corresponding video frame.

13. The system as recited in claim 12 , wherein the unmixed hash value is included in a transmission packet carrying the video frame.

14. The system as recited in claim 12 , wherein the unmixed hash value is included in a header extension of an RTP packet transporting the video frame.

15. The system as recited in claim 10 , wherein the hashing means further comprises an MFCC function.

16. One or more computer storage media embodied with executable instructions that, when executed, implement the following method: hashing an audio frame of an audio signal to derive an unmixed hash value; combining the unmixed hash value with a video frame of a video signal, the video frame corresponding to the audio frame; transmitting the audio frame to a receiver over an analog network; and transmitting the video frame and the unmixed hash value to the receiver over a digital network wherein the unmixed hash value is included in a SIP (Session Initiation Protocol) packet with a corresponding video frame number.

17. The one or more computer storage media as recited in claim 16 , wherein the hashing step further comprises applying an MFCC function to the audio frame.

18. The one or more computer storage media as recited in claim 16 , wherein the analog network farther comprises a PSTN and the digital network further comprises an IP network.